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Phil Lewis

Bio: Phil Lewis is an academic researcher from Oklahoma State University–Stillwater. The author has contributed to research in topics: Fuel efficiency & Diesel fuel. The author has an hindex of 17, co-authored 42 publications receiving 908 citations. Previous affiliations of Phil Lewis include Texas A&M University & North Carolina State University.

Papers
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Journal ArticleDOI
TL;DR: The importance of accounting for intercycle variability in real-world in-use emissions to develop more accurate emission inventories is demonstrated by the development and demonstrated for deployment of a portable emission measurement system for excavators.
Abstract: A study design was developed and demonstrated for deployment of a portable emission measurement system (PEMS) for excavators. Excavators are among the most commonly used vehicles in construction activities. The PEMS measured nitric oxide, carbon monoxide, hydrocarbons, carbon dioxide, and opacity-based particulate matter. Data collection, screening, processing, and analysis protocols were developed to assure data quality and to quantify variability in vehicle fuel consumption and emissions rates. The development of data collection procedures was based on securing the PEMS while avoiding disruption to normal vehicle operations. As a result of quality assurance, approximately 90% of the attempted measurements resulted in valid data. On the basis of field data collected for three excavators, an average of 50% of the total nitric oxide emissions was associated with 29% of the time of operation, during which the average engine speed and manifold absolute pressure were significantly higher than corresponding averages for all data. Mass per time emission rates during non-idle modes (i.e., moving and using bucket) were on average 7 times greater than for the idle mode. Differences in normalized average rates were influenced more by intercycle differences than intervehicle differences. This study demonstrates the importance of accounting for intercycle variability in real-world in-use emissions to develop more accurate emission inventories. The data collection and analysis methodology demonstrated here is recommended for application to more vehicles to better characterize real-world vehicle activity, fuel use, and emissions for nonroad construction equipment.

128 citations

Journal ArticleDOI
TL;DR: In this paper, a portable emissions monitoring system was used to collect fuel use and emissions data from eight backhoes, six bulldozers, three excavators, four generators, six motor graders, three off-road trucks, one skid-steer loader, three track loaders, and five wheel loaders while they performed various duty cycles.
Abstract: Limited field data are available for analyses of fuel use and emissions of nonroad diesel construction equipment. This paper summarizes the results of field research that used a portable emissions monitoring system to collect fuel use and emissions data from eight backhoes, six bulldozers, three excavators, four generators, six motor graders, three off-road trucks, one skid-steer loader, three track loaders, and five wheel loaders while they performed various duty cycles. These tests produced approximately 119 h of field data for petroleum diesel and approximately 48 h for B20 biodiesel. Engine attribute data including horsepower, displacement, model year, engine tier, and engine load were collected to determine these factors' influence on fuel use rates and emission rates of nitrogen oxides, hydrocarbons, carbon monoxide, carbon dioxide, and opacity. Mass per time fuel use rates were developed for each item of equipment, as were mass per time and mass per fuel used emission rates for each pollutant. For ...

112 citations

Journal ArticleDOI
TL;DR: In this article, the authors introduce the chall... The purpose of this paper is to quantify the levels of emissions that nonroad construction vehicles and equipment produce, based on existing data sources (such as the EPA NONROAD model) or by collecting data directly from the vehicles as they work in the field.
Abstract: Nonroad construction vehicles and equipment powered by diesel engines contribute to mobile source air pollution. The engines of this equipment emit significant amounts of carbon monoxide, hydrocarbons, nitrogen oxides, and particulate matter. These pollutants pose serious problems for human health and the environment. Therefore, it is necessary to regulate and control the levels of these pollutants. Furthermore, there are emerging requirements and incentives for “greening” of construction vehicle fleets and operations. Currently, there are two types of standards that regulate air pollution for these types of vehicles: technological standards for engines and quality standards for air. It is also necessary to quantify the levels of emissions that nonroad construction vehicles and equipment produce. Quantification may be based on existing data sources (such as the EPA NONROAD model) or by collecting data directly from the vehicles as they work in the field. The purpose of this paper is to introduce the chall...

98 citations

Journal ArticleDOI
TL;DR: In this paper, the impact of engine idling on fuel use and CO2 emissions of diesel construction equipment is quantified in terms of equipment operational efficiency, defined as the ratio of non-idle time to total equipment use time.
Abstract: It is difficult to quantitatively assess the impact of engine idling on fuel use and emissions of construction equipment because of a lack of sufficient data. This paper presents a methodology for evaluating the impact of idling on fuel use and carbon dioxide ( CO2 ) emissions of diesel construction equipment. The results are based on field data collected from 34 items of equipment. Engine idle time may be quantified in terms of equipment operational efficiency ( η ), which is defined as the ratio of nonidle time to total equipment use time (nonidle time plus idle time). Using η and the ratio of idle to nonidle fuel use and CO2 emission rates ( r ), the percentage increase in the total quantities of fuel used and CO2 emitted ( NE ) were calculated for each item of equipment for values of η less than the maximum theoretical operational efficiency of 100%. Results showed that as η decreased (or idle time increased), NE increased. A mathematical model that uses η as a predictor variable was developed to esti...

79 citations

Journal ArticleDOI
TL;DR: An empirical modal-based model of vehicle fuel use and emissions was developed, based on stratifying the data with respect to ranges of normalized MAP, to enable comparisons between duty cycles, motor graders, and fuels.
Abstract: Motor graders are a common type of nonroad vehicle used in many road construction and maintenance applications. In-use activity, fuel use, and emissions were measured for six selected motor graders using a portable emission measurement system. Each motor grader was tested with petroleum diesel and B20 biodiesel. Duty cycles were quantified in terms of the empirical cumulative distribution function of manifold absolute pressure (MAP), which is an indicator of engine load. The motor graders were operated under normal duty cycles for road maintenance and repair at various locations in Wake and Nash Counties in North Carolina. Approximately 3 hr of quality-assured, second-by-second data were obtained during each test. An empirical modal-based model of vehicle fuel use and emissions was developed, based on stratifying the data with respect to ranges of normalized MAP, to enable comparisons between duty cycles, motor graders, and fuels. Time-based emission factors were found to increase monotonically with MAP. Fuel-based emission factors were mainly sensitive to differences between idle and non-idle engine operation. Cycle average emission factors were estimated for road "resurfacing," "roading," and "shouldering" activities. On average, the use of B20 instead of petroleum diesel leads to a negligible decrease of 1.6% in nitric oxide emission rate, and decreases of 19-22% in emission rates of carbon monoxide, hydrocarbons, and particulate matter. Emission rates decrease significantly when comparing newer engine tier vehicles to older ones. Significant reductions in tailpipe emissions accrue especially from the use of B20 and adoption of newer vehicles.

72 citations


Cited by
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Journal Article
TL;DR: A case study explores the background of the digitization project, the practices implemented, and the critiques of the project, which aims to provide access to a plethora of information to EPA employees, scientists, and researchers.
Abstract: The Environmental Protection Agency (EPA) provides access to information on a variety of topics related to the environment and strives to inform citizens of health risks. The EPA also has an extensive library network that consists of 26 libraries throughout the United States, which provide access to a plethora of information to EPA employees, scientists, and researchers. The EPA implemented a reorganization project to digitize their materials so they would be more accessible to a wider range of users, but this plan was drastically accelerated when the EPA was threatened with a budget cut. It chose to close and reduce the hours and services of some of their libraries. As a result, the agency was accused of denying users the “right to know” by making information unavailable, not providing an adequate strategic plan, and discarding vital materials. This case study explores the background of the digitization project, the practices implemented, and the critiques of the project.

2,588 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present a review of the existing green BIM literature and outline the most important directions for future research, and suggest that a "one-stop-shop" BIM for environmental sustainability monitoring and management over a building's full life cycle should be considered.

416 citations

Journal ArticleDOI
TL;DR: In this article, the authors compared the level of CO2 emission caused by the construction activities globally by using the world environmental input-output table 2009 and analyzed CO2 emissions of construction sector in 40 countries, considering 26 kinds of energy use and non-energy use.
Abstract: The construction sector delivers the infrastructure and buildings to the society by consumption large amount of unrenewable energy. Consequently, this consumption causes the large emission of CO2. This paper explores and compares the level of CO2 emission caused by the construction activities globally by using the world environmental input-output table 2009. It analyses CO2 emission of construction sector in 40 countries, considering 26 kinds of energy use and non-energy use. Results indicate: 1) the total CO2 emission of the global construction sector was 5.7 billion tons in 2009, contributing 23% of the total CO2 emissions produced by the global economics activities. 94% of the total CO2 from the global construction sector are indirect emission. 2) Gasoline, diesel, other petroleum products and light fuel oil are four main energy sources for direct CO2 emission of global construction sector. The indirect CO2 emission mainly stems from hard coal, nature gas, and non-energy use. 3) The emerging economies cause nearly 60% of the global construction sector total CO2 emission. China is the largest contributor. Moreover, the intensities of construction sector’s direct and indirect CO2 emission in the developing countries are larger than the value in the developed countries. Therefore, promoting the development and use of the low embodied carbon building material and services, the energy efficiency of construction machines, as well as the renewable energy use are identified as three main pivotal opportunities to reduce the carbon emissions of the construction sector.

347 citations

Journal ArticleDOI
TL;DR: A computer vision based algorithm for recognizing single actions of earthmoving construction equipment, based on a multiple binary SVM classifier and spatio-temporal features, which outperforms previous algorithms for excavator and truck action recognition.

215 citations

Journal ArticleDOI
TL;DR: In this paper, a fuel-based approach is used to estimate exhaust emissions of nitrogen oxides (NOx) and fine particulate matter (PM2.5) from mobile sources in the United States for the years 1996-2006.
Abstract: [1] A fuel-based approach is used to estimate exhaust emissions of nitrogen oxides (NOx) and fine particulate matter (PM2.5) from mobile sources in the United States for the years 1996–2006. Source categories considered include on-road and off-road gasoline and diesel engines. Pollutant emissions for each mobile source category were estimated by combining fuel consumption with emission factors expressed per unit of fuel burned. Over the 10-year time period that is the focus of this study, sales of gasoline and diesel fuel intended for on-road use increased by 15 and 43%, respectively. Diesel fuel use by off-road equipment increased by ∼20% over the same time period. Growth in fuel consumption offset some of the reductions in pollutant emission factors that occurred during this period. For NOx, there have been dramatic (factor of 2) decreases in emission factors for on-road gasoline engines between 1996 and 2006. In contrast, diesel NOx emission factors decreased more gradually. Exhaust PM2.5 emission factors appear to have decreased for most engine categories, but emission uncertainties are large for this pollutant. Diesel engines appear to be the dominant mobile source of both NOx and PM2.5; the diesel share of total NOx has increased over time as gasoline engine emissions have declined. Comparing fuel-based emission estimates with U.S. Environmental Protection Agency's national emission inventory led to the following conclusions: (1) total emissions of NOx and PM2.5 estimated by two different methods were similar, (2) source contributions to these totals differ significantly, with higher relative contributions coming from on-road diesel engines in this study.

180 citations